Abstract
A steam injector (SI) is a passive jet pump with no movable parts, able to drive water by supersonic steam jet, reaching a discharge pressure even higher than the supply steam pressure. Moreover the SI works as a direct contact heat exchanger between steam and water. We have developed multi-stage SIs by using steam directly extracted from the turbine, which has high performance in wide operation range and can be used in parallel-operation to simplify feed-water heating system of nuclear and thermal-power plant. In this study, we carried out endurance test in order to verify the performance and resistance of the SI under operation during prolonged time period. The SI has undergone a global amount of 80 hours operation with steam and no performance degradation has been evidenced. According to inspection of inner parts of SI, good resistance of the component was shown in continuous operation under conditions similar to those for which it is designed.
